feat(board): ORDRE and FLY carry the age of the oldest order

Both columns were pure counts (ls | wc -l), so ORDRE 2 read identically
whether both orders arrived yesterday or both had sat for ten days. The
defect was never that orders sit there - that is a prioritisation
question owned by humans. It was that no surface showed the AGE ACROSS
REPOS: coord-order-inbox.sh does show one, but only inside the one repo
at SessionStart, so a repo nobody opens shows nobody anything.

Measured across the live mailbox 2026-08-29 with `find ~/.claude/coord
-path '*/orders/*.md' -maxdepth 3 -type f`: 30 pending orders over 22
repos, 5 of them ten days old. Re-measured here after this session
consumed two of them: 29 over 23 mailboxes, still 5 at ten days. The
residual delta is not attributable from this repo - the mailbox has
other writers - and is reported rather than reconciled away.

Rendered N:Md. This is not a new mechanism in the file: ALDER (STATE.md
mtime) and SISTE (last commit) already read a clock the same way.

The age is the OLDEST order, never the newest and never a mean - a repo
holding one fresh order and one ten-day-old order has a ten-day-old
problem, and the newest reading is exactly what would hide it. FLY
carries the identical reading, and there it matters at least as much:
nothing un-claims an order when the session that took it dies, so a
claim with no age is the 117-hour claim with its only counter-evidence
removed.

An empty queue prints a BARE 0, never "0:0d": "no orders" and "an order
that arrived today" are different facts, the same reason FLY exists
beside ORDRE. An unreadable mtime prints "?" for the WHOLE reading
rather than skipping the file, because an unmeasured file could be the
oldest one - the same token coord-count and DRT already use.

NO NEW SORT AXIS. The age is display-only; putting it in the ranking
would silently reorder a parser living in another repo. --plan's fly=
and every other emitted key=value block are untouched: the requirement
is that a human reading the board sees an order is old without opening
the repo, and the table is where that is read. Nothing here writes -
board.sh stays read-only, and no cron, hook or notifier was added.

TDD: board-selftest.sh section 28 written first and RED before board.sh
was touched. It builds a throwaway coord tree with touch -t mtimes and
asserts its OWN ground truth (the stale fixture really is 10 days old)
before anything depends on it. Known-positive control: a second repo
with two genuinely fresh orders, so the 10d assertion is proven able to
fail. Mutation-verified: flipping -lt to -gt in oldest_order_age turns
exactly the two oldest-specific checks red, all controls green.

Four pre-existing assertions in board-selftest and orders-selftest
matched the old bare-count cell and were updated to the N:Md form; the
claim each pins - INN, ORDRE and FLY are never summed - is unchanged.

Suites under real /bin/bash 3.2: board 325/325 (was 314), coord 242/242,
route 69/69, orders 110/110, guard 54/54. npm test 11/11.

No version bump, no tag, no catalog ref - as ordered.

Order: 20260829T045435Z-276822386-from-.claude

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

scripts/orders-selftest.sh

@@ -336,7 +336,7 @@ printf '%s' "$bout" | grep -q 'ordrepo'; check "board table lists the fixture re
 # Matched on the rendered row rather than by awk field number: KOST is
 # "Sonnet 5/high", which contains a space, so a field index would be counting
 # the wrong columns and would keep "passing" if the layout shifted.
-printf '%s' "$bout" | grep -qE '^ordrepo[[:space:]]+planned[[:space:]]+Sonnet 5/high[[:space:]]+1[[:space:]]+2[[:space:]]'
+printf '%s' "$bout" | grep -qE '^ordrepo[[:space:]]+planned[[:space:]]+Sonnet 5/high[[:space:]]+1[[:space:]]+2:0d[[:space:]]'
 check "board prints INN 1 and ORDRE 2 side by side, never summed" $?
 
 # --dispatch --order-id: the thin starter form. The order text lives in the